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Green Line Travel Time Update

Yesterday evening, I boarded a route 50 bus at Minnesota and 6th Street in downtown Saint Paul at 4:43 p.m. and rode it to the University of Minnesota campus, getting off at Oak Street and Washington Avenue. That was at 5:29 p.m., or 46 minutes after I had boarded in Saint Paul. The bus still had about three miles to go before ending its run in downtown Minneapolis. Under a schedule posted last weekend, the Green Line is supposed to make an equivalent trip (Central station to East Bank station) in 31 minutes. The bus was 48% slower than the current expectation for LRT (and the 50 is a limited-stop route—the 16 is even slower).

Metro Transit posted updated bus schedules for routes along the Green Line as my last article went up, and posted the schedule for the Green Line itself last weekend. I’ve updated my graphs from that last entry to show expected downtown-to-downtown travel times:

Eastbound, with the existing schedules and old Green Line projection first, and current planned Green Line and route 94 schedules second (the 50 will be replaced by the Green Line—the 16 will still exist, but won’t run downtown-to-downtown, and therefore can’t be compared):

Westbound, with the existing schedules and old Green Line projection first, and current planned Green Line and route 94 schedules second (again, the 16 will still exist, but won’t run downtown-to-downtown, and therefore can’t be compared):

I also went a bit further and tried to show how the frequency of service affects these travel times. These graphs assume that you’ve arrived at the bus stop halfway between two runs of the same service—if you’re a punctual person (and the services are running on time), these times may be able to be shortened a bit. I didn’t try to account for people switching between different services (16 to 50 for instance), and assumed that people would typically take the next route 94 rather than keeping track of whether it’s a B, C, or D:

The good news is that the Green Line should be faster than the old routes 16 and 50 by a big margin, except it may be a bit slower late at night (11 p.m. to 5 a.m.). Morning/evening commuters using route 94 should also see some improvement—particularly in making travel times more consistent—as that route is being realigned to use 5th and 6th streets in downtown Saint Paul, won’t have the split of some routes running up to the Capitol and back, and will use 7th Street for westbound runs into downtown Minneapolis rather than jogging over to 4th Street. However, the frequency of service for route 94 has been cut back in midday so that it’s not much different than taking the Green Line, and evening service after 7 p.m. has been eliminated—those service hours have been folded into increasing frequency on lines that criss-cross the LRT route, such as the 87, 84, and new route 83.

Of course, we’ll have to wait until the first days/weeks of service to really know how these travel times work out. With more than 60 intersections and other signaled locations where the trains can be forced to stop, just removing or adding an average of one second across all of those signals can change the Green Line’s end-to-end travel time by a minute. Slight errors in setup can be magnified, so it’s critical that signals are configured correctly.

The Green Line will be around for decades to come (and hopefully longer than that!), so we shouldn’t too be dismayed by hiccups at the start. It will take a consistent effort to improve and maintain good travel times along the corridor, though.

We may also see changes to related services—the 16 and 94 in particular. Will we keep the 16 in its truncated, lower-frequency state (becoming every 20 minutes most of the day rather than every 10 minutes as it is today)? Will the 94 still have a reduced frequency at midday? That route might get folded into future Red Rock or Gateway Corridor bus services.

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About Mike Hicks

Mike Hicks is a computer geek at heart, but has always had interests in transportation and urban planning. A longtime contributor to Wikipedia, he started a blog about trains and other transportation after realizing it had been two decades since he'd first heard about a potential high-speed rail line from Chicago to Minneapolis. Read more at http://hizeph400.blogspot.com/

10 Responses to Green Line Travel Time Update

The thing you realize about this signal timing tweaking going on right now is that the final ‘timing priorities’ that they eventually settle on remain arbitrary. How do we decide who gets to wait and for how long at intersections? What priorities do planners and decision makers place on different modes?

My point is that, if we wanted to, we could shave even more time off the Green Line’s journey. It’s a question of political will and mode prioritization.

I guess this is a way of asking: What is the theoretical shortest possible run time for the Green Line?

Ever since I started seeing speed limit signs go up along the tracks over the winter, I’ve been thinking of mapping out all of the different sections and trying to model that in a computer somehow. It shouldn’t be too hard… It’s always a good idea to have some schedule padding beyond the absolute best possible travel time, though.

Along University Avenue, the tracks are generally signed for 35 mph, but go down to 20 mph in the immediate vicinity of station platforms. The curve at Fairview is signed for 25, and sharper turns seem to be signed at 10 mph. I think the downtowns are generally 20 or 25, and there are other subtleties here and there.

Does anyone have an inkling about how well trains will perform in downtown Minneapolis? I think signal prioritization in downtown Minneapolis is really important. With alternating Blue and Green line trains every couple minutes or so, there’s no reason a train should be at the mercy of traffic lights at either of the 2nd or 3rd Avenues, or any of the other avenues. Any red light a train has to wait for in DT Minneapolis seems needless.

Having been working on the signal timing on the Minneapolis portion of the Green Line I can tell you that the system is designed primarily to maintain safety at intersections. Following that, the signals are programmed to minimize delays for the trains while respecting other users of the intersections. You may already know that Minneapolis has chosen to use “Portland style” LRV priority…trains should not stop at traffic signals under normal operation.

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